Insulating tubular covering and method of making the same



C- A. DE VYVER INSULATING TUBULAR COVERING AND METHOD OF MAKING THE SAME Jan. 18, 1949.

Filed June 1, 1946 I NVENTOR. Corne/l'us A. deVy ven' ATTORNEY.

Patented Jan. 18, 1949 INSULATING TUBULAR GGV-E'RLING D METHOD -OF"MAKING I HE"SMIE Cornelius-A. vde Vyver, Chappaqua, N ills assignor to lohns-lvlanville Corporation, N

,ew 'York,

'N. Y., a corporation of NewiYork Application J me 1, 1946,S'erial3No.-"-673;801

Claims. (01.166-1H0 The present invention wings and to a-method of their manufacture and has for its 3Drincipa1=obj8ct the provision of an improved, tubular insulating covering for pipes,

tubesiand othersimilar lines; for example, water,

oiliandiair 'linesand the like. The tubular covering-.in thejpreferred embodiment of the invention is flexible and may be fed lengthwise onto a pipe and conformed to the irregularities and curvatures thereof. v

iAnother.objectiofztherinvention is the provision of ,an insulating covering including a "tubular layer of insulatingmaterial 'and a .fiexiblesleeve enclosing and confining the tubular layer.

Aiiurther object of theinventionis the provisionxif acovering ofithetype referred toin which the insulating layer iscomposedof a preformed, felted, 'fibrousmaterial, such ashair .felt, mineral wool rich, .or the like. A .still .further object of the invention is the .provision of a method of making "such .covering, the method .involving the application of the preformed, .felted material in strip form .to a-mandrl, .the shaping of. the materiaharoundthemandrl to -'form a tubular layer, and theiknitting of .a seamless-sleeve around the layeridflinsulating material. My invention will .be more fully understood and further pbjects and advantages thereof will .become apparent when reference is made .to the more ,detailed description of a .preferred embodiment of the invention which is to fo'llow-and to theeaccompanyingdrawingiin which: r

.l .iSlaZperspeQtiVe view-6f aztubularcnver of :an element -of the particularly tor use as an insulation- ;for .pipes,

tubes and the :like. The ,pro'duct :is used, for example, for covering copper waterrlines z-employed in wehicles, rhuildings sand-ether structures a1- though :as will he appreciated, iiteis adaptedto serve :otnerepurposes. lllh'e ooveringi'zinoludes v -a relates to insulating covtuhuiar'insulatin'g layer l2-and an outersleeve 44 of gpreferably seamless, flexible construction, enclosing Rand confining the insulating layer. If desired, a waterproof coating 16 maybe applied over ethevsleeve to r retard or :prevent the pen etration of moisturerinto the insulating material and to :give the covering 'a ifinished appearance. Coating rmateri-als .such as wbitumens, rubbers, glues, vinyl resins, natural or synthetic gums or resins and-theiike maybe used for this purpose, the-selection of sthe particular "coating depending .upon ttheyparticular characteris'tics desired.

insulating-layer l2 is composed of a preformed, self-sustaining, felted fib'rous material such as a conventional hair felt, mineral wool felt, glass feltaor-tlre like. ithe felt may include asuitable hinder to maintain the inter-felted relationship characters l8 and 19in the formof the inve-m tion. illustrated in Fig. l.

Strips 18 and 20 are trapezoidallin rcross secti'on whereby, when they -arevdeiormed.transverselyitodefine tube sections,

with itheireshortest base dimensions at the interior of r-tlre :tube, their adjacent edges meet in radial planes. A strip of the preferred crosssectionalrshape isillustratedin Fig. 4.

Sleeve M is formed of a flexible, distortable, seamless fabric and :suitably is a knitted tube. iBheknittirig-strandsare-selected toimpart to the product the desired .properties or characteristics, but preferably *are fine wires :or cut strands of metal or alloys of metal The harder metals or alloys, such as steel, nichrome, monel metal, inconel and-the like, may be used'where the coveringdsto 'ibeisubjected to extremely high temperatures. 0n ithe oth'er than-d, if the covering is to be rempioydd (under aordinary, 01 reasonably high temperature acon'ditions, softer metals such as copper, or even textile strands, including asbestos strands, cotton strands, or the like, may be employed. Where metal strands are used as is preferred, relatively fine strands, say, those having a diameter of about 0.006", are selected, and the fabric is preferably knitted to have relatively small mesh openings, for example, mesh openings of about A stood that the gauge of the strands and the size of the stitches may vary considerably.

Referring now particularly to Figs. 2 and 3, the method of forming the tubular covering is illustrated. The method is carried out with suitable apparatus including a stationary mandrel 22, supported from some fixed portion of the frame as by bracket 24, and having a free, unsupported end 26. The mandrel is in the form of a rod of circular cross-section and extends centrally through a circular knitting machine of known strand material from which the sleeve 14 is. to be fabricated are supported from the machine, as indicated, to be rotated around the cylinder, the strand extending from the supply through a guide 34 to the knitting point. The drive for the knitting machine, the supporting members and other conventional operating parts, such as the needle cam structure,and the like, have not been shown, and the knitting machine elements referred to have been shown only diagrammatically, as such features may be of any conventional known type and, per se, form no part of the invention.

Supported above the knitting machine are forming members 36 and 38 comprising rollers mounted for, preferably, free rotation on supporting shafts 4i! and 42, respectively. 'Rollers 36 and 38 are provided on their circumferential surfaces with grooves 44 of semi-circularcrosssection, the grooves, when the rollers are in substantially contacting relationship as illustrated in Fig. 3 defining a circle concentric to the mandrel and of substantially the outer diameter of the tubular insulating layer. Below the knitting machine is a take-off device 46 comprising opposed, knurled rolls driven from any suitable source (not shown). I

In the operation of the device as thus far described, strips i 8 and are fed from suitable supplies between the forming rolls and the mandrel, the latter serving to deform or longitudinally wrap the strips around the mandrel and'to bring the edges of the strips into adjacent relationship. As the strips pass below the forming members they may spring apart to some extent but will approximate a tube. This tube is threaded through the knitting machine and then through the rolls of the take-off device. The

knitting machine is then placed in'operatiorrand the take-off device driven in timed relationship to the operation of the knitting machine. The take-off rolls cause a constant downward movement of the strips from the supplies and through the forming device and the knitting machine. -As the approximately cylindrical tube passes through th knitting machine, sleeve I4 is knitted around it, the resilient characteristics of the knitted fab ric forcing the sections of the insulating layer into closely adjacent relationship to define a true tube.

Where a coating i6 is desired, the selected coating material is applied by coating device 48 which may take any suitable form but, as shown, includes a housing 50 supported from the frame of the apparatus and enclosing a, spray ring 52 con- I-Iowever, it will be under-' nected with any suitable source of coating supply (not shown) by coating line 54. The coating is sprayed on the covering as the latter passes through the spray ring, the coating forming a protective layer overlying the knitted mesh and also penetrating the interstices of the mesh, at least to some extent. Directly below the coating device and suitably connected to it is a setting chamber 56. The setting chamber may be of any construction and length required to dry or set the particular coating material applied by Boater 50. As shown,;.th'e chamber in the :jforinoi an extended tube having inlet and outlet ports 58 and 60, respectively, through which a setting medium such as steam, hot air, or the like may be circulated, to 'coznpletely or substantially completely continuous length, as described above, may be cut into units of any suitable size for selected purposes. The tube is flexible and may be readily threaded onto the extended pipe lines to con form to their irregularities and curvatures. The operation is economical and may be carried out at high speed. I

Having thus described my invention in rather full detail, it will be understood that these details neednot be strictly-adhered to but that various changes and modifications may suggest themselves to one skilled in' the art, all falling within the scope of the invention as defined by the subjoined claims. a

What I claim is:

l. A flexible, tubular covering composed of a felted, preformed, self-sustaining, fibrous'material forminga tubular'layer, and an enclosing and confining sheath comprising a seamless sleeve. v i

A flexible, tubular covering comprising a felted, preformed, self-sustaining, fibrous, material defining a tubular layer and a knitted sleeve enclosing and confining said layer. 3. AQ flexible," tubular covering 'comprising'a felted, preformed, self-sustaining, fibrous; material defining a tubularlayer, a sleeve of knitted metal mesh enclosingand confining saidlayeri sleeve of metal mesh enclosing and and a waterproof coating on said sleeve. I. I ,4...A flexible, tubular covering comprising, an insulating layer including preformed, self-Sus taining, felted, fibrous material shaped into tubu lar form, and a'knitted sleeve of metal mesh enclosing and confining said material in its tubular form. y I

5. A flexible insulating covering comprising an insulating layer including preformed, selfsus-j taining, felted strips shaped transversely to joint 1y "define a tube, and a knitted sleeve enclosing and confinin'g'said layer in its tubular form."- 6. An insulating, tubular covering comprising an insulating layer including preformed, felted strips, trapezoidal in cross-section and shaped transversely to jointly define a tube, and a knitted confining said layer in its tubular form.

'7. An insulating, tubular covering comprising an insulating layer including preformed, felted strips, trapezoidal in cross-section and shaped transversely to jointly define a tubefa knitted sleeve ofmetal mesh enclosing and 'conflning'said layer in its tubular form, and a waterproof coat ing on said sleeve.-

8. The method'of forming atubular covering comprising applying felted, self-sustainingrin' sulating material to a mandrel to extend 1onsi 5 tudinelly thereof and to form a tube, and knitting a sleeire around said tube. 7

9. The method of forming a tubular insulating covering comprising feeding flat, self-sustaining strips of felted, fibrous material between forming rolls and a mandrel to conform said strips to said mandrel and to form a tube, and knitting a seamless sleeve around said tube.

10. The method of forming, a tubular insulating covering comprising feeding fiat, self-sustaining strips, trapezoidal in cross-section between forming rolls and a mandrellto conform said strips to said mandrel and to form a tube, and knitting a seamless sleeve around said tube.

CORNELIUS A. or: VYVER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

